Enables clean VM shutdown.

runtime/vm/isolate.cc

Index: runtime/vm/isolate.cc
diff --git a/runtime/vm/isolate.cc b/runtime/vm/isolate.cc
index 5071b6cd5f367ffdded29b40407fdda3d7df080a..8ece4f532e6a01d33fb68d673bc6b6df56cb1101 100644
--- a/runtime/vm/isolate.cc
+++ b/runtime/vm/isolate.cc
@@ -5,6 +5,7 @@
 #include "vm/isolate.h"
 
 #include "include/dart_api.h"
+#include "include/dart_native_api.h"
 #include "platform/assert.h"
 #include "platform/json.h"
 #include "vm/code_observers.h"
@@ -157,7 +158,6 @@ class IsolateMessageHandler : public MessageHandler {
   bool IsCurrentIsolate() const;
   virtual Isolate* isolate() const { return isolate_; }
 
- private:
   // Keep both these enums in sync with isolate_patch.dart.
   // The different Isolate API message types.
   enum {
@@ -178,6 +178,7 @@ class IsolateMessageHandler : public MessageHandler {
     kAsEventAction = 2
   };
 
+ private:
   // A result of false indicates that the isolate should terminate the
   // processing of further events.
   bool HandleLibMessage(const Array& message);
@@ -742,6 +743,7 @@ void Isolate::InitOnce() {
   create_callback_ = NULL;
   isolates_list_monitor_ = new Monitor();
   ASSERT(isolates_list_monitor_ != NULL);
+  creation_enabled_ = true;

[turnidge, 2015/08/04 21:39:02]

Consider calling EnableIsolateCreation here?

[zra, 2015/08/05 06:23:06]

Done.

 }
 
 
@@ -814,8 +816,13 @@ Isolate* Isolate::Init(const char* name_prefix,
     result->compiler_stats_ = new CompilerStats(result);
   }
   ObjectIdRing::Init(result);
-  // Add to isolate list.
-  AddIsolateTolist(result);
+
+  // Add to isolate list. Shutdown and delete the isolate on failure.
+  if (!AddIsolateToList(result)) {
+    result->Shutdown();
+    delete result;
+    return NULL;
+  }
 
   return result;
 }
@@ -1458,7 +1465,10 @@ void Isolate::Shutdown() {
     HandleScope handle_scope(this);
 
     // Write out the coverage data if collection has been enabled.
-    CodeCoverage::Write(this);
+    if ((this != Dart::vm_isolate()) &&
+        !ServiceIsolate::IsServiceIsolateDescendant(this)) {
+      CodeCoverage::Write(this);
+    }
 
     if ((timeline_event_recorder_ != NULL) &&
         (FLAG_timeline_trace_dir != NULL)) {
@@ -1555,7 +1565,7 @@ Dart_EntropySource Isolate::entropy_source_callback_ = NULL;
 
 Monitor* Isolate::isolates_list_monitor_ = NULL;
 Isolate* Isolate::isolates_list_head_ = NULL;
-
+bool Isolate::creation_enabled_ = true;

[turnidge, 2015/08/04 21:39:02]

Maybe we should start this as false.

[zra, 2015/08/05 06:23:06]

Done.

 
 void Isolate::IterateObjectPointers(ObjectPointerVisitor* visitor,
                                     bool visit_prologue_weak_handles,
@@ -1904,12 +1914,16 @@ intptr_t Isolate::IsolateListLength() {
 }
 
 
-void Isolate::AddIsolateTolist(Isolate* isolate) {
+bool Isolate::AddIsolateToList(Isolate* isolate) {
   MonitorLocker ml(isolates_list_monitor_);
+  if (!creation_enabled_) {
+    return false;
+  }
   ASSERT(isolate != NULL);
   ASSERT(isolate->next_ == NULL);
   isolate->next_ = isolates_list_head_;
   isolates_list_head_ = isolate;
+  return true;
 }
 
 
@@ -1931,7 +1945,9 @@ void Isolate::RemoveIsolateFromList(Isolate* isolate) {
     previous = current;
     current = current->next_;
   }
-  UNREACHABLE();
+  // If we are shutting down an isolate that tried to start after the VM
+  // started going down, then it may not be in the list.

[turnidge, 2015/08/04 21:39:02]

I feel like there is a simpler version of this comment out there... maybe...

// If we are shutting down the VM, the isolate may not be in the list.

[zra, 2015/08/05 06:23:06]

Done.

+  ASSERT(!creation_enabled_);
 }
 
 
@@ -1945,9 +1961,33 @@ void Isolate::CheckForDuplicateThreadState(InterruptableThreadState* state) {
     current = current->next_;
   }
 }
+
+
+int Isolate::IsolateCount() {
+  MonitorLocker ml(isolates_list_monitor_);
+  Isolate* current = isolates_list_head_;
+  int count = 0;
+  while (current) {
+    count++;
+    current = current->next_;
+  }
+  return count;
+}
 #endif
 
 
+void Isolate::DisableIsolateCreation() {
+  MonitorLocker ml(isolates_list_monitor_);
+  creation_enabled_ = false;
+}
+
+
+void Isolate::EnableIsolateCreation() {
+  MonitorLocker ml(isolates_list_monitor_);
+  creation_enabled_ = true;
+}
+
+
 template<class T>
 T* Isolate::AllocateReusableHandle() {
   T* handle = reinterpret_cast<T*>(reusable_handles_.AllocateScopedHandle());
@@ -1956,6 +1996,61 @@ T* Isolate::AllocateReusableHandle() {
 }
 
 
+void Isolate::KillIsolate(Isolate* isolate) {
+  Dart_CObject kill_msg;
+  Dart_CObject* list_values[4];
+  kill_msg.type = Dart_CObject_kArray;
+  kill_msg.value.as_array.length = 4;
+  kill_msg.value.as_array.values = list_values;
+
+  Dart_CObject oob;
+  oob.type = Dart_CObject_kInt32;
+  oob.value.as_int32 = Message::kIsolateLibOOBMsg;
+  list_values[0] = &oob;
+
+  Dart_CObject kill;
+  kill.type = Dart_CObject_kInt32;
+  kill.value.as_int32 = IsolateMessageHandler::kKillMsg;
+  list_values[1] = &kill;
+
+  Dart_CObject cap;
+  cap.type = Dart_CObject_kCapability;
+  cap.value.as_capability.id = isolate->terminate_capability();
+  list_values[2] = &cap;
+
+  Dart_CObject imm;
+  imm.type = Dart_CObject_kInt32;
+  imm.value.as_int32 = IsolateMessageHandler::kImmediateAction;
+  list_values[3] = &imm;
+
+  isolate->ScheduleInterrupts(Isolate::kMessageInterrupt);
+  Dart_PostOOBCObject(isolate->main_port(), &kill_msg);
+}
+
+
+class IsolateKillerVisitor : public IsolateVisitor {
+ public:
+  IsolateKillerVisitor() {}
+
+  virtual ~IsolateKillerVisitor() {}
+
+  void VisitIsolate(Isolate* isolate) {
+    ASSERT(isolate != NULL);
+    if (ServiceIsolate::IsServiceIsolateDescendant(isolate) ||
+        (isolate == Dart::vm_isolate())) {
+      return;
+    }
+    Isolate::KillIsolate(isolate);
+  }
+};
+
+
+void Isolate::KillAllIsolates() {
+  IsolateKillerVisitor visitor;
+  VisitIsolates(&visitor);
+}
+
+
 static RawInstance* DeserializeObject(Isolate* isolate,
                                       Zone* zone,
                                       uint8_t* obj_data,